Java tutorial
/* From http://java.sun.com/docs/books/tutorial/index.html */ /* * Copyright (c) 2006 Sun Microsystems, Inc. All Rights Reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * -Redistribution of source code must retain the above copyright notice, this * list of conditions and the following disclaimer. * * -Redistribution in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. * * Neither the name of Sun Microsystems, Inc. or the names of contributors may * be used to endorse or promote products derived from this software without * specific prior written permission. * * This software is provided "AS IS," without a warranty of any kind. ALL * EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES, INCLUDING * ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE * OR NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN MIDROSYSTEMS, INC. ("SUN") * AND ITS LICENSORS SHALL NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE * AS A RESULT OF USING, MODIFYING OR DISTRIBUTING THIS SOFTWARE OR ITS * DERIVATIVES. IN NO EVENT WILL SUN OR ITS LICENSORS BE LIABLE FOR ANY LOST * REVENUE, PROFIT OR DATA, OR FOR DIRECT, INDIRECT, SPECIAL, CONSEQUENTIAL, * INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER CAUSED AND REGARDLESS OF THE THEORY * OF LIABILITY, ARISING OUT OF THE USE OF OR INABILITY TO USE THIS SOFTWARE, * EVEN IF SUN HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. * * You acknowledge that this software is not designed, licensed or intended * for use in the design, construction, operation or maintenance of any * nuclear facility. */ /* * DragListDemo.java is a 1.4 example that requires the following file: * ArrayListTransferHandler.java */ import java.awt.BorderLayout; import java.awt.Dimension; import java.awt.datatransfer.DataFlavor; import java.awt.datatransfer.Transferable; import java.awt.datatransfer.UnsupportedFlavorException; import java.io.IOException; import java.util.ArrayList; import javax.swing.BorderFactory; import javax.swing.DefaultListModel; import javax.swing.JComponent; import javax.swing.JFrame; import javax.swing.JList; import javax.swing.JPanel; import javax.swing.JScrollPane; import javax.swing.ListSelectionModel; import javax.swing.TransferHandler; public class DragListDemo extends JPanel { ArrayListTransferHandler arrayListHandler; public DragListDemo() { arrayListHandler = new ArrayListTransferHandler(); JList list1, list2; DefaultListModel list1Model = new DefaultListModel(); list1Model.addElement("0 (list 1)"); list1Model.addElement("1 (list 1)"); list1Model.addElement("2 (list 1)"); list1Model.addElement("3 (list 1)"); list1Model.addElement("4 (list 1)"); list1Model.addElement("5 (list 1)"); list1Model.addElement("6 (list 1)"); list1 = new JList(list1Model); list1.setSelectionMode(ListSelectionModel.SINGLE_INTERVAL_SELECTION); list1.setTransferHandler(arrayListHandler); list1.setDragEnabled(true); JScrollPane list1View = new JScrollPane(list1); list1View.setPreferredSize(new Dimension(200, 100)); JPanel panel1 = new JPanel(); panel1.setLayout(new BorderLayout()); panel1.add(list1View, BorderLayout.CENTER); panel1.setBorder(BorderFactory.createEmptyBorder(5, 5, 5, 5)); DefaultListModel list2Model = new DefaultListModel(); list2Model.addElement("0 (list 2)"); list2Model.addElement("1 (list 2)"); list2Model.addElement("2 (list 2)"); list2Model.addElement("3 (list 2)"); list2Model.addElement("4 (list 2)"); list2Model.addElement("5 (list 2)"); list2Model.addElement("6 (list 2)"); list2 = new JList(list2Model); list2.setSelectionMode(ListSelectionModel.SINGLE_INTERVAL_SELECTION); list2.setTransferHandler(arrayListHandler); list2.setDragEnabled(true); JScrollPane list2View = new JScrollPane(list2); list2View.setPreferredSize(new Dimension(200, 100)); JPanel panel2 = new JPanel(); panel2.setLayout(new BorderLayout()); panel2.add(list2View, BorderLayout.CENTER); panel2.setBorder(BorderFactory.createEmptyBorder(5, 5, 5, 5)); setLayout(new BorderLayout()); add(panel1, BorderLayout.LINE_START); add(panel2, BorderLayout.LINE_END); setBorder(BorderFactory.createEmptyBorder(20, 20, 20, 20)); } /** * Create the GUI and show it. For thread safety, this method should be * invoked from the event-dispatching thread. */ private static void createAndShowGUI() { //Make sure we have nice window decorations. JFrame.setDefaultLookAndFeelDecorated(true); //Create and set up the window. JFrame frame = new JFrame("DragListDemo"); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); //Create and set up the content pane. DragListDemo demo = new DragListDemo(); frame.setContentPane(demo); //Display the window. frame.pack(); frame.setVisible(true); } public static void main(String[] args) { //Schedule a job for the event-dispatching thread: //creating and showing this application's GUI. javax.swing.SwingUtilities.invokeLater(new Runnable() { public void run() { createAndShowGUI(); } }); } } /* * ArrayListTransferHandler.java is used by the 1.4 DragListDemo.java example. */ class ArrayListTransferHandler extends TransferHandler { DataFlavor localArrayListFlavor, serialArrayListFlavor; String localArrayListType = DataFlavor.javaJVMLocalObjectMimeType + ";class=java.util.ArrayList"; JList source = null; int[] indices = null; int addIndex = -1; //Location where items were added int addCount = 0; //Number of items added public ArrayListTransferHandler() { try { localArrayListFlavor = new DataFlavor(localArrayListType); } catch (ClassNotFoundException e) { System.out.println("ArrayListTransferHandler: unable to create data flavor"); } serialArrayListFlavor = new DataFlavor(ArrayList.class, "ArrayList"); } public boolean importData(JComponent c, Transferable t) { JList target = null; ArrayList alist = null; if (!canImport(c, t.getTransferDataFlavors())) { return false; } try { target = (JList) c; if (hasLocalArrayListFlavor(t.getTransferDataFlavors())) { alist = (ArrayList) t.getTransferData(localArrayListFlavor); } else if (hasSerialArrayListFlavor(t.getTransferDataFlavors())) { alist = (ArrayList) t.getTransferData(serialArrayListFlavor); } else { return false; } } catch (UnsupportedFlavorException ufe) { System.out.println("importData: unsupported data flavor"); return false; } catch (IOException ioe) { System.out.println("importData: I/O exception"); return false; } //At this point we use the same code to retrieve the data //locally or serially. //We'll drop at the current selected index. int index = target.getSelectedIndex(); //Prevent the user from dropping data back on itself. //For example, if the user is moving items #4,#5,#6 and #7 and //attempts to insert the items after item #5, this would //be problematic when removing the original items. //This is interpreted as dropping the same data on itself //and has no effect. if (source.equals(target)) { if (indices != null && index >= indices[0] - 1 && index <= indices[indices.length - 1]) { indices = null; return true; } } DefaultListModel listModel = (DefaultListModel) target.getModel(); int max = listModel.getSize(); if (index < 0) { index = max; } else { index++; if (index > max) { index = max; } } addIndex = index; addCount = alist.size(); for (int i = 0; i < alist.size(); i++) { listModel.add(index++, alist.get(i)); } return true; } protected void exportDone(JComponent c, Transferable data, int action) { if ((action == MOVE) && (indices != null)) { DefaultListModel model = (DefaultListModel) source.getModel(); //If we are moving items around in the same list, we //need to adjust the indices accordingly since those //after the insertion point have moved. if (addCount > 0) { for (int i = 0; i < indices.length; i++) { if (indices[i] > addIndex) { indices[i] += addCount; } } } for (int i = indices.length - 1; i >= 0; i--) model.remove(indices[i]); } indices = null; addIndex = -1; addCount = 0; } private boolean hasLocalArrayListFlavor(DataFlavor[] flavors) { if (localArrayListFlavor == null) { return false; } for (int i = 0; i < flavors.length; i++) { if (flavors[i].equals(localArrayListFlavor)) { return true; } } return false; } private boolean hasSerialArrayListFlavor(DataFlavor[] flavors) { if (serialArrayListFlavor == null) { return false; } for (int i = 0; i < flavors.length; i++) { if (flavors[i].equals(serialArrayListFlavor)) { return true; } } return false; } public boolean canImport(JComponent c, DataFlavor[] flavors) { if (hasLocalArrayListFlavor(flavors)) { return true; } if (hasSerialArrayListFlavor(flavors)) { return true; } return false; } protected Transferable createTransferable(JComponent c) { if (c instanceof JList) { source = (JList) c; indices = source.getSelectedIndices(); Object[] values = source.getSelectedValues(); if (values == null || values.length == 0) { return null; } ArrayList alist = new ArrayList(values.length); for (int i = 0; i < values.length; i++) { Object o = values[i]; String str = o.toString(); if (str == null) str = ""; alist.add(str); } return new ArrayListTransferable(alist); } return null; } public int getSourceActions(JComponent c) { return COPY_OR_MOVE; } public class ArrayListTransferable implements Transferable { ArrayList data; public ArrayListTransferable(ArrayList alist) { data = alist; } public Object getTransferData(DataFlavor flavor) throws UnsupportedFlavorException { if (!isDataFlavorSupported(flavor)) { throw new UnsupportedFlavorException(flavor); } return data; } public DataFlavor[] getTransferDataFlavors() { return new DataFlavor[] { localArrayListFlavor, serialArrayListFlavor }; } public boolean isDataFlavorSupported(DataFlavor flavor) { if (localArrayListFlavor.equals(flavor)) { return true; } if (serialArrayListFlavor.equals(flavor)) { return true; } return false; } } }